People like to say that DEs have made a comeback. I don't really think they have. They are still non-existant in the mainstream of shaving products. Most people under 35 don't know what they are, and they can't be found in the average drug store. They are strictly a niche market. Look of 'long tail market' and you will probably see Double Edged Safety razors as an example.
But if they really do catch on and become popular again, do you think Gillette would manufacture them again?